[FIX] base_import: handle other cases of wrong CVS mime types
[FIX] base_import: handle other cases of wrong CVS mime types

Improves 8049d1e855204c64b56577ecdc32f838f494474c for other detected
cases, e.g. on Firefox + OSX.

opw-680347

hip-odoo/odoo,laslabs/odoo,Elico-Corp/odoo_OCB,microcom/odoo,ygol/odoo,bplancher/odoo,laslabs/odoo,bplancher/odoo,laslabs/odoo,dfang/odoo,bplancher/odoo,Elico-Corp/odoo_OCB,microcom/odoo,microcom/odoo,hip-odoo/odoo,hip-odoo/odoo,ygol/odoo,bplancher/odoo,microcom/odoo,Elico-Corp/odoo_OCB,laslabs/odoo,microcom/odoo,ygol/odoo,ygol/odoo,laslabs/odoo,dfang/odoo,dfang/odoo,storm-computers/odoo,storm-computers/odoo,laslabs/odoo,storm-computers/odoo,Elico-Corp/odoo_OCB,bplancher/odoo,ygol/odoo,hip-odoo/odoo,ygol/odoo,storm-computers/odoo,storm-computers/odoo,dfang/odoo,Elico-Corp/odoo_OCB,hip-odoo/odoo,ygol/odoo,dfang/odoo,bplancher/odoo,dfang/odoo,hip-odoo/odoo,Elico-Corp/odoo_OCB,storm-computers/odoo,microcom/odoo